Reinforced concrete construction.



l\'o. 890,428. PATENTED JUNE 9, 1908.

J. W. LINZEE, JR.

EEINPORCED CONCRETE CONSTRUCTION.

APPLICATION FILED MAR. 29, 1907.

2 SHEETS-SHEET 1.

No. 890,428. PATENTED JUNE 9, 1908. J. W. LNZBE, JR.,

-REINPORCED CONCRETE GUNSTRGTIQN.

APPLICATION ILED MAILZQ, 1907.

2 SHEBTS*SHBET 2,

"UNITED STATES PATENT onirica.

JOHN W. LINZEE, JR., OF BOSTON, MASSACHUSETTS.

IREINFORCIEIDy CONCRETE CONSTRUCTION.

l Specification of Letters Patent.

Patented June 9, 1908.

Application led March 29, 1907. Serial No. 365,347.

To all -whom it may concern: Y

. Be it known that I, JOHN W. LiNzEE,Jr., of Boston, inthe county of Suffolk and State of Massachusetts, have invented certain new and useful Improvements in Reinforced Concrete Constructions, of which the following is' a specification.

This invention relates to concrete' and steel constructions, bein particularly appli- Table for ioor beams, arc es and trusses, and -also capable of' employment inwalls, columns, etc.

The object is to reinforce concrete beams by means of longitudinal tension bars and transverse shear bars so as to rovide for the roper transference of stress om the shear Ears intofthe. concrete and into the horizontal bar more directly than hitherto, and as an aid to skin friction..

Another object is to bend the sheai bars in termediate their ends so as to form from them elements which are respectively inclined and perpendicular to the longitudinal bars, thereby combining in a single structure the 'principle of inclined tension bars with vertical concrete compression members, together with the princi le' of the vertical tension bars with incline concrete compression members, the constructions embodying these principles being in dierent planes and connecte together so that the concrete in all parts of the structure may be subjected only to compression, While all the tensile stresses are taken by the metal, so as to obtain the maximum 'strength with the minimum eX- penditure oi` material, and to avoid useless weight. Y

A further. object is to arrange the inclined member of each shear bar so as to overlap the vertical member or members of adjacent bars so as to form a net-work whereby it will be impossible to pass a section through the structure transverse to the longitudinalbar without cutting' a shearbar before or simultaneously with the cutting of the longitudinal bar, for the purpose of resisting the shearing stresses by members r.arranged so as to oppose their tensile strength to vsuch stresses.

The accompanyin drawings showv a number of ways in whic the 'ob`ects and principles of my invention may e carried out.

Figures .1 and 2 represent sectional` views of concrete beams with longitudinal tension,v

rods and a variety of arrangements of shearI bars engaged therewith for .carrying stresses transverselyof the beam. Fig. 3 represents a longitudinal sectional elevation showing the manner in which certain of the shear bars in Figs. 1 and 2 are arranged. Fig. 4 represents a sectional plan view of* the structure shown in Fig. 1. Figs. 4a and 4b represent vertical sections taken on planes A-B and O-D, respectively of Fig. 4. Fi 5 represents a cross section illustrating t e manner in which'onev of the connectionsbetween the tension and shear bars may be used as a spacing means. Figs. 6 and 7 represent. in detail a' ragmentary section and elevation of one form of connection between the tension and shear bars. Figs. 8 and 9 represent similar views of a moriiication of this connection. Fig. 10 represents .in elevation a further modiiicationfy Fig. 11 represents a sectional view of another modication. Fi 12 re resentsasectional elevation ofafurt er mo iicationof the same principle. Figs. 13, 14

and 15 represent two elevations and a cross.

section of a construction embodying similar principles in which a separate tie member is em loyed.

he saine reference characters indicate the same arts in all the figures.

Re erring rst to Figs. 1, 2, 3, 4, 4, 4b and 5, c represents a concrete beam which is to be structure in which are embedded longitudinal tension bars b c and d, and transverse shear bars e andf. Each ofthe shear bars is bent intermediate its ends and passes artially around one or moreof the longitu in'al bars, being embedded atits ends in the concrete adjacent the opposite side of the structure from the longitudinal bars. As indicated above, th'e lon itudinal barslie in the angles formed by the ends in the shear bars. The latter arefurther twisted or bent in longitudinal planes so as to form elements which are respectively inclined and er endicular to the longitudinal bars. A At ie yfigures show the structure as a horizontal beam with the longitudinal bars b c and d horizontal, and portionsfof the shear bars as vertical, and therefore for convenience, the terms horizontal and' vertical will be used hereinafter in the specification to avoid circumlocution, it bein that the longitudinalars may be either horizontal as when in a beam, or vertical as in a wall or column, and that the term vertical77 when appliedto a shear bar means perpendicular to the longitudinal bar.

understood, however,

85 "understood as being typical ofvany concrete In every construction, whether two or more longitudinal bars are used, Athe shear bars are so located as to forni res ectively inclinedeandvertical members.r wo" elements of the same shear bar may be respec.

tively inclined and vertical, as illustrated in Figs. 3, 4, 4a, and 4b, or both the elements of ment crosses 'or overla s the'vertical element of the adjacent bar.

have onl inclined shear bars, a plane such as his forms a net-work, as illustrated in Fig. 3, so that itis impossible to pass a transverse plane through the structure withoutcutting both a shear bar and the'longitudinal bar.` In constructions which A-B V( ig... 3)l could be passed without'cutanymetal except `the longitudinal bars,

' whlle whenonly vertical shear bars are em.-

ployed,`a 'vert1cal plane`-likeCD can be gasse'd without intersecting the shear Ibar.

tresses 4 tending to shear the structure may loccur 'on leither of thesel planes, which with the older constructions would be resisted fmainlyy by the concretefx' Thisresistance would be very slight in the c'ase vof the vertical shear plane, since'theresistance to shear-. ing of concrete is slight. construction herein' illustrated, a truss is-` formed of steel bars in which any'transverse With the network stress is opposed by a component of theten.- Sile -strengt tion ofthe structure is`without 'a shear bar.

An'o'therresult which is` derived from having 'the inclined and vertical elements'res'pectively, is that of combining in a single strucvture'two standard tri 1 'ss`syst em`s. to' Fig.l "4"`, which' illustrates a section taken. on line A-B of Fig. 4 vas viewed inthe directions forA securingthey shear bars anditenston tion of the arrow, the inclined` elements of the shear bars e are 'shownbetwe'en whichthe concrete f orni's verticalfstruts to supportthe 3 loadingon-the ppe'r'side ofthe structure, v als in the ratt`tru`ss system. Fig. Allfillustrates the central section of the beam lookin infthe direction ofthe arre'wfromthe line Cf- Q, In this figure the vertical elementsof the shear bars are shown 'which are in tension, i.While the concrete'between the metal elements is `in' compression on diagonal lines (illustrated by the arrows), forming inclinedfstruts.` of concrete asinthe Howe truss lsystem 1 The `outer section olthebeaniiin which thein-f clined members of shear barsf lie, yi'slthesame as shown in Fig. 4a. vThusthe strueture is formed of a 'series of trusses in which, the sev-v eral systems alternate, whichfl'are tied together by the transverse 'portions ofthe'shir@ rods' uniting the verticalV and inclinedele-` ments respectively-i' 'Tie laisses ...ofthernetal bars are therebytransferred to theI concrete, and vice versa, in the most effective possible manner so as to utilize practi- "carr'y all tensile stresses in the metal.

ina't least 'one of the shear bars.- This isdue to the fact that no transverseseceferring cally all the concrete in compression, and 'to n this Way beams and other structures may be made "lighter4 and with greater economy of material.. l

It is'` to be understood that the reverse of the construction shown in Figs. 4, 4.a and 4" may be employed,` that is, thatthe outer members maybevertical and; the inner' ones inclined. the inclined members extend Supwardly toward the nearest end of thebeam, soithat on opposite sides of the ,center their inclinations are op osite, thus {following'iout the'v usual 4princlp es of vtru ss`construction.A i ,.-f

Fig. 2 showsa construction in which-the .trussprinciple i s,ex` tended so as to form a truss 1n cross-section. Here theshearbars `are not only provided with vertical and inclined elements, but certain elements .such as those Vdesignatedeefl .andfa1 are' inclined transe versely also vso that theyzoverlapfin'crosssection and transfer stresses .fromon'eside of the trussto the ot her.-, -The members e3/and f 3 may be either perpendicularto-.the 4longitudinals .or inclined vwith respect .thereto `toward the adjacentendbf thefbeam...;`r

In Fig. 5, the s ,liearbar eHpasses-underthe three .lon itudinal bars b cxand IZ, andiisiprovidedY with Wedges twhicnenter. slots in {the distance apart; As this shearbar affords no L connection for `thecentral longitudinal, a 4shearbar f is yprovided yiii-the .center of; the `b eamwhichis bent about .thecentral bar c.

Qertainof the members 'ottheseshiear- .bars are inclined, While others are,vertical..V Thus, the membersofr-the b ar eimayffb'othibeeinclined,l while both end svof, f Vare vertical; or ythe reverse may lbethel case. .f-if..

., I will now proceed ,toidescribethefconnecbars together. Y .n

In each of the figures numbered :6.tol15 inclusive, thetensionbarv` is represented-by t andthe Isheanbar by .e In Figsa'and 7f,-

r the shear bars are formed with integral wedge tongues i on theinner-surface'Ofthecentral v part. of the bend inythelshear4 bari. These V tongues enter slots,l indentationsf,` onrecesses inthe under side; of the tensionfbar, and .when -driven in by theblowA of a hammer, 'are held fritionally and. prevent slipping of. one

bar relatively to the other- A.j `There must rbe enough metal 1n the Wed ge tongue to takethe It is to'oeborne in mind also-that longitudinals, and keepythematthe: proper horizontal compo nent of the stress inthe shear.`

A bar and transferit to the tensionzbar without danger-.of stripping ,off the. tongue. At the points k Where the recesses or slots lj in the tenslonbarhare formed, the bar is enlarged,

Ahaving enough 'metal in theprotuberances if? A tto. compensatejfon the amountremoved; in

makingthe recesses y'. Such enlargements also serve as anchors for the longitudinal bars, preventing endwise movement thereof lpoints, but are preferably fiattened at the contacting' points, or they may be still further flattened'and widened, as shown inl Fig. 10. i

Figs. Sand 9 show the shear bars carried around so as to entirely surround the tension bar and are crowded together above the latter by a Wedge collar ZL I In Fig. 11, the wedge i is separate and is driven through the shear 'bar before entering the socket j in the tension bar. Theshear bars shown in these figures are preferably bent on aV radius of curvature less than that of the tension bar at the zone of engagement. Thus when they are forced together, the tension bar spreads apart the members of the shear bar, putting ythe outer elements of these members under `a compressive strain whereby they' are held'tightlyv against the tension bar and grip it frictionally, which assists the wedges in tightly securing the bars together. A

Fig.'12 shows a reversal of the construction above illustrated, iny which the wedge is formed 'on the tension bar andy is forced into a socket in the shear bar.

In Figs. 13, 14:V and 15 the shearbar does not embrace the tension bar, but is held may be omitted altogether.

against the top of the latter by a binding ring or collar n. 'The top of the tension bar is preferably flattened, and the side of the shear bar which comes next it is` also flattened to provide an extended bearing and prevent twisting. `Either the lugs 0r wedgetongue may be 'provided to secure the ring to the tension bar, while the shearbar is frictionally wedged between the ring and tension bar, having an enlargement o at the point where it `is bent for this purpose. An integral wedge protuberance p may also be formed upon the tensionbar to increasey the wedging action between the latter and thev shear bar, and if desired, the wedge ton uei lf this is one, the shear bar and ring are forced horizontally over the enlargement p so as to secure a tight engagement of the wedging action of the latter.

lt will be noted that in Figs. 6 to 12 inclusive, the sides of the socket y' embrace the wedge-tongue i and act as shoulders or abutments which restrain the tongue against movement in any direction, while the enlargement o on the shear bar, and p on the tension bar, constitute integral wedges or abutments which by means of the ring n bind the bars together.

l-n Fig. 5, the principle of the tongue and slot connection is illustratedvas applied to a beam in which there are three longitudinal tension bars, and a single shear bar passing under all three of them. It may also be appliedv where there are merel than three or where there are only two longitudinals. In any case, the wedges serve as spacers to keep the longitudinal Ibars at the proper dlstance apart, and as securing means to prevent slipping of the shear bars alonlg the longitudlnals. It is to be understood that one or another of these securing .connections is .intended to be used with each of the shear bars in the arrangements shown in Figs. 1, 2 l

and 3.

1. Inl a reinforced concrete struc-ture, the combination of a'plurality of longitudinal tension bars in the same horizontal plane, and shear bar elements in different vertical longitudinal planes, the elements in one of the vertical lanes being vertical and those in another p ane being inclined, and the adjacent vertical and inclined elements in the different lanes being connected yby integral horizontal)` transverse connecting members beneath the longitudinal bars; the ysaid constructionformin parallel truss systems bonded together by t e connecting members.

2. In a reinforced concrete structure, the combination of a plurality of longitudinal tension bars in one plane, shear bar elements respectively perpendicular and inclined with respect to said longitudinal bars arrangedin separated longitudinal parallel planes perpendicular tothe first-named plane, the perpendicular shear bar elements bcing'in one of the parallel planes and the inclined members in another, whereby parallel truss systems are provided, and direct transverse connecting members integrally uniting the perpendicular and inclined elements of each couple together, said elements and members embracing alplurality of longitudinal bars and resisting separation thereof with the entire tensile strength of the transverse members.

3. In a reinforced concrete structure, the combination of a plurality of longitudinal tension bars spaced apart from each other, and shear bars bent to form three sides of an embracing structure Within which at least two of the longitudinal members are included the outer elements at one end of said shear bars being inclined to the longitudinal bars and lying in one plane which includes one of the longitudinal bars, forming therewith a truss having intermediate vertical concrete struts the elements at the opposite ends of the shear bars being in a different plane, parallel to the first-named plane, with another longitudinal bar and perpendicular thereto, forming therewith a truss having intermediate inclined concrete struts; and the intermediate members of the shear bars eX- tending straight fromcne plane to the other and bonding the truss structures together.

t, In a reinforced concrete structure, a longitudinal tension bar, a shear bar bent at an y angle so as to form a vertical and an inclined tension element, engaging the longitudinal bar at thebend, and anjmtegral Wedge formed on one ofthe bars coacting with the other bar ,at-the point ,ofl engagement, to prevent rela-` tive motion. p i

` A5. In areinforced concrete structure, the combination of longitudinal tension bars and transverse Shear bars bent to inclose a bar and. to. form members extending throughout nearly' the entire thickness of the concrete,

vcertain of said members being yinc-lined and ars having protuberances at the bends and ythe longltudlnal bars ,having slots to receive said protuberances, the longitudinal bars being enlarge'dat the points Where the slots are formed, whereby thetensile strength of these bars is preserved and anchoring enlargements are provided.

6. In a reinforced concrete structure, the- .combination of longitudinal and transverse members, certain of said members havmg 1n-` dentations extending partially therethrough,

and having an enlargement adjacent each mdentation and on the sideo positeV thereto, and other ofthe members raving Wedging projections adapted to be readily inserted in the indentations, Whereb)T the membersmay be readilv assembled during `the construction l of the Work.

7. A reinforcing structure for concrete 'consisting of longltudmal and transverse members, certam of said members havmg slots at -intervals throughout their length and the other of said members having protuberances extending into, and gripped by the walls of,

saidslots, andv them'embers in which the slots are formed having compensating enlargements adjacent the slots.

8. A reinforcing structure for concrete consisting of separate reinforcing members, certain of 'said members having integral Wedges and the other members having correspondingly shaped slots into which said members are driven, and by which they are gripped thereby preventing motion at their point of contact.

9. 'In a reinforced concrete structure, a longitudinal tension bar, a shear bar having a bend and being engaged with the longitudinal bar at the bend, a Wedge member on said shear bar adjacent to the bend, and a cooperating abutment on'the longitudinal bar with which said wedge member is engaged.

10. In a reinforced concrete structure, a longitudinal tension bar, a shear bar having a bend and being engaged with the longitu- .dinal bar at the bend, a Wedge member on said shear bar adjacent to the bend, a coperating abutment on the longitudinal bar with which said Wedge member is engaged, and a collar surrounding said shear bar to retain the Wedge member and abutment in contact. I y

11.. In a reinforcedlfconcrete structure, a longitudinal tension bar, a shear bar bent about said longitudinalv bar and provided with a Wedgeentering a slot in the longitudinal bar,and a collar surrounding the membersof the shear bar adjacent to the longitudinal'bar for causing the shear bar to grip the longitudinal bar.

In testimony whereof I have ,affixed my signature, in presence of two witnesses.

JOHN W. LINZEE, JR.

Y Witnesses A. C. RATIGAN, ARTHUR H. BROWN. l 

